Point 12 of my 12 point list of methods for reducing cracking in portland cement stucco
Point twelve - Work must be done by experienced people.
This should say enough. If you are a DIY it means that you should be ready to accept the consequences, including bad work, or the fact your time is only worth $3.00 per hour. I understand the frustration of homeowners or contractors when people don't show up or do what they are supposed to do. Also, there is a severe shortage of qualified plasterers, but still it is worth the wait for quality.
Other reasons for excessive cracking:
Finish coat cracking:
Too much lime in the finish coat, mortar too rich in the finish, sand too fine.
Most cracks only occur in the finish coat. These superficial cracks may not be a large danger of water infiltration, they can be avoided.
Lack of bond:
This is a source of larger deeper cracks, and loose areas.
Frequent causes of lack of bond:
Finish coat doesn't bond when resurfacing. We see a lot of this.
Brown coat too slick.
Bonding agent failure.
Inexperience.
Excessive cracking in the brown coat:
Sand in the brown coat too dirty or too fine. Sand should be a yellow color and not too fine. A reddish or a dirty brown color indicates too much red clay or dirt in the sand.
Sand in the brown coat too dirty or too fine.
Thanks so much to Paul and Melissa from Louisiana to put all the points into one downloadable .pdf file.